September 13, 2017 9:27am EDTSeptember 13, 2017 7:54am EDTThere's an old adage in baseball that says you shouldn't trust what you see in March or September. Well, thanks to the surging Indians and the plummeting Dodgers, this September will put baseball's conventional wisdom to the test.Kenta Maeda(Getty Images)

There's an old adage in baseball that you shouldn't trust what you see in March or September. Well, that'll be put to the test this season, thanks to the surging Indians and the plummeting Dodgers.

The logic behind the adage is sound: Appearances can be deceiving with the season's bookends. A .450 hitter in spring training, no matter how good he looks, is not actually a .450 hitter. A hot team in September, no matter how dominant it appears, is guaranteed nothing in October. A cold team in September, no matter how horribly it plays, can still win the World Series. You get the idea.

But never in baseball history have we seen contenders display the kinds of simultaneous extremes of the Indians and Dodgers. Their respective hot and cold streaks can sure tempt one to conclusion jump. But, as we know, things can change in a hurry in baseball, and teams/players almost always end up being exactly what we thought they were. Is it safe to assume that's how things will play out in 2017? Hard to say, but it's sure going to be interesting.

At the least, that old adage about September is wisdom that should keep the Indians (and their fans) humble amid a historic streak and should keep the Dodgers (and their fans) from losing their minds as they're enveloped by the opposite kind of history. And it's history itself that tells us October is, literally, a whole new ballgame. More on that in a bit.

Judging by September appearances, the Indians will plow through the season's final weeks and bring Cleveland its long-sought championship with ease. Meanwhile, if we're going by appearances, the Dodgers will lose three straight in the Division Series (if they even make it!) and crawl sheepishly into the winter. Neither is likely to happen.

As you know, Cleveland is on a 20-game winning streak, one win from setting the all-time American League record, and looking like an unstoppable force. Everything is clicking: The pitchers have produced six shutouts during the streak, and the team has a collective OPS of .942. Dominant stuff.​

The Dodgers, as you also know, look terrible. Entering play Tuesday, they had lost 11 straight — their longest such streak of the Los Angeles era — and 16 of their past 17. Just a month ago, LA was a slam dunk to fly past 100 wins and was in the discussion as perhaps the greatest team of all time. Now, the Dodgers look as though they could struggle to reach the century mark. Woof.

The September hot: The 2002 A's, whose 20-game winning streak the Indians matched Tuesday, were scorching going into September and going out. After winning their 20th straight on Sept. 4, they finished the month 18-7 (including winning nine of 11 to close out the season) and tallied an MLB-best 103 wins — in prime position to win in October. Then they lost in the Division Series.

The September cold: The 2000 Yankees went 2-13 over their last 15 games — including seven straight losses to end the season. After going 8-2 to open the month, the bottom fell out and the team stumbled to just 87 total wins. And they didn't just lose, the were blown out — a lot. Starting with an 11-1 loss to the Indians on Sept. 15, the Yankees' pitching staff allowed 11 or more runs seven times (including three instances of 15 or more) while the offense was held to two or fewer runs eight times. New York looked vulnerable, even terrible. Then they won the World Series.

There are less extreme examples, too. The 1993 Braves went 22-8 over their final 30 games to win the NL West and surge into the playoffs with 104 wins. Atlanta never even lost more than one game at a time during that stretch, as they had three future Hall of Fame pitchers leading the way. Still, they lost in six games to the Phillies in the NLCS, the only round of league playoffs at the time.

On the other side, the 2006 Tigers went 12-16 over their last 30 games, including five straight losses to end the season, which dropped them into second place on the final day after leading their division by as many as 10 games in August. Simply put: They blew it. Talk about limping into the playoffs with a bruised ego. They still went to the World Series, though.

Here's the point: September doesn't matter once the calendar turns to October. Nothing is certain. We all know this. So keep it together, Cleveland and Los Angeles. Things may look great/horrible now, but there's still a long way to go.